找到数组的大小 [英] Find the size of an array

问题描述

我想创建一个相同大小的数组的新数组

可用：

#include< stdio.h>

#include< string.h>


int main（无效）

{

char arrc [] =" ; URI" ;;

const int asize = sizeof（arrc）/ sizeof（arrc [0]）;

char new_arr [asize];


printf（" new_arr size =％d \ n"，sizeof（new_arr））;


返回0;

}


========================输出============== ======

[arnuld @ dune C] $ gcc4 -ansi -pedantic -Wall -Wextra test.c

test.c：在函数中？ maina ??：

test.c：9：警告：ISO C90禁止可变大小数组a ?? new_arra ??

[arnuld @ dune C] $ ./ a.out

new_arr size = 4

[arnuld @ dune C] $


该程序给出正确答案。但为什么警告。 sizeof（）编译

时间运算符然后为什么我得到一些与运行时相关的警告？



-
www.lispmachine.wordpress.com

我的电子邮件是@上面的博客。

Google Groups现在是UnBlocked :)

I want to create a new array of the same size of an array already
available:
#include <stdio.h>
#include <string.h>

int main(void)
{
char arrc[] = "URI";
const int asize = sizeof(arrc) / sizeof (arrc[0]);
char new_arr[asize];

printf("new_arr size = %d\n", sizeof(new_arr));

return 0;
}

======================== OUTPUT ====================
[arnuld@dune C]$ gcc4 -ansi -pedantic -Wall -Wextra test.c
test.c: In function a??maina??:
test.c:9: warning: ISO C90 forbids variable-size array a??new_arra??
[arnuld@dune C]$ ./a.out
new_arr size = 4
[arnuld@dune C]$

The program gives correct answer. But Why the warning. sizeof() is compile
time operator then why do I get some warning related to run-time ?


--
www.lispmachine.wordpress.com
my email is @ the above blog.
Google Groups is UnBlocked now :)

推荐答案

gcc4 -ansi -pedantic -Wall -Wextra test.c

test.c：在函数中?? ?? maina ??：

test.c：9：警告：ISO C90禁止变量大小的数组a ?? new_arra ??

[arnuld @ dune C]

gcc4 -ansi -pedantic -Wall -Wextra test.c
test.c: In function a??maina??:
test.c:9: warning: ISO C90 forbids variable-size array a??new_arra??
[arnuld@dune C]

./ a.out

new_arr size = 4

[arnuld @ dune C]

./a.out
new_arr size = 4
[arnuld@dune C]

程序给出正确答案。但为什么警告。 sizeof（）编译

时间运算符然后为什么我得到一些与运行时相关的警告？



-
www.lispmachine.wordpress.com

我的电子邮件是@上面的博客。

谷歌群组现在是UnBlocked :)

The program gives correct answer. But Why the warning. sizeof() is compile
time operator then why do I get some warning related to run-time ?


--
www.lispmachine.wordpress.com
my email is @ the above blog.
Google Groups is UnBlocked now :)

这篇关于找到数组的大小的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！